Wheat straw left after harvesting of edible mushroom Pleurotus ostreatus
was evaluated as feed for growing lambs. Twenty four weaned lambs (25.75 +/- 5
kg) were randomly assigned to two treatments: 70% of wheat straw, either raw
(US) or upgraded by Pleurotus ostreatus (TS) plus 30% of a concentrate mixture.
Lambs were fed the diets for 60d. Feed intake, BW gain and feed conversion (FC)
were measured. In situ digestibility of DM, NDF, ADF, and in vivo DM
digestibility were also evaluated. The results showed no difference (P>0.05)
in feed intake (1.65 and 1.59 kg day(-1) for US and TS, respectively), with a
lower (P<0.05) BW gain for TS (4.75 +/- 0.406 kg) than for US (6.06 +/-
0.401 kg) accompanying a poorer FC (US 16.91; TS 22.18). In vivo digestibility
of DM was similar (P>0.05) for both treatments (76.43% US, 76.16% TS), as
were the data on in situ digestibility of DM, NDF, and ADF after 12, 24, 36,
48, and 72h of incubation in the rumen. In conclusion, it could be said that
wheat straw treated by Pleurotus ostreatus did not improve its nutritional
value when fed to growing lambs.

Lychee (Litchi chinensis Sonn.) is a fruit originating from China and
Vietnam which is cultivated in Mexico also, and Veracruz is cultivated with
“Mauritius” and “Brewster” cultivars and it is the main state for the national
and international markets. The aim of this research was to evaluate the
physical and chemical characteristics of lychee fruits produced in six orchards
located at the central and northern regions of the state of Veracruz. For this
study 4 kg were sampled per each orchard, from which 40 fruits were randomly
selected for quality evaluation. The variables measured were: length, diameter,
firmness, weight of fruit and its components (e.g. pulp, peel and seed), total
soluble solids, titratable acidity, and pericarp color. The “Mauritius” fruits
varied in quality amongst orchards. The Lechuguillas orchard showed the biggest
fruits with 35.1 mm length, 21.2 g of total weight and 16.8 g of pulp weight. Furthermore,
fruits of this site had low acidity, acceptable peel color and high content of
total soluble solids.

Neotropical bracken fern invades disturbed forests and burned and abandoned
pastures in Latin America, inhibiting the growth of associated vegetation and
altering community structure. Cutting of all aboveground vegetation every 6 to
12 mo has proven to be inefficient as a control method. We studied the impact
of selective cutting of bracken every 2 mo, shading, and a combination of
cutting + shading during 14 mo in a bracken-dominated, abandoned pasture in Veracruz,
Mexico. At the end of the experiment, cutting with or without shading
drastically reduced bracken cover from >90% to less than 1%, decreased leaf
number from 18 to fewer than two leaves per m(2), and depleted bracken leaf
biomass. The significant reduction of bracken was correlated with a significant
3.9- to 5.7-fold increase in richness of other plant species. Cutting without
shading was the only treatment that significantly reduced rhizome biomass to
less than 62% of control plots, whereas cutting + shading was the only
treatment to promote a significant increase in both cover and shoot biomass of
successional plant species. Selective cutting of P. arachnoideum repeated every
2 mo was more successful than nonselective cuttings repeated at longer intervals,
because it removed newly emerging leaves before their complete expansion and
supported the recovery and reestablishment of other plant species, which may
help to control bracken. Although costs for the first year of selective cutting
were twice as much as for nonselective cutting, it may prove less expensive and
more efficient than nonselective cutting in the long term.

Cedrela odorata L. is a species distinguished by the quality of its wood.
Cedar established in the field must adapt to changes in resource availability;
survival is greater when the root system is associated with microorganisms that
improve nutrition and growth. The aim of this study was to evaluate the effect
of Rhizophagus intraradices and Azospirillum brasilense on the growth of C.
odorata and its nitrogen (N) and phosphorus (P) uptake capacity. Cedar seeds
were sown in pots in accordance with the following treatments: control,
15(N)-15(p)-15(K) fertilization, R. intraradices, A. brasilense, R.
intraradices + A. brasilense, and R. intraradices + A. brasilense + A.
brasilense + 15(N)-15(p)-15(K) fertilization. Morphological and physiological
yield variables and root colonization were recorded every 28 days, and N and P
contents at the end of the experiment (140 days). In general, R. intraradices
promoted greater plant growth (P <= 0.05) of morphological and physiological
yield components. The maximum height (97 cm) was recorded in plants with R.
intraradices + A. brasilense + 15(N)-15(p)-15(K) fertilization, representing 40
% more height than the control. N and P increased with the inoculation of the
microorganisms alone and combined.

The xoconostle (Opuntia matudae Scheinvar) is a sour fruit, of which the
peel is consumed. It is perishable, but it has a beneficial effect on human
health, as recognized popularly in Mexico. The objective of this study was to
create a snack of dried xoconostle using neotame, an artificial non-caloric
sweetener, to improve flavor. We present (a) a partial chemical
characterization of the fruit (total phenolic content (TP) and antioxidant
activity (AA)), (b) dehydration techniques (heating by convection and
freeze-drying), and (c) sensorial characterization of the final product. The
experimental unit was 40 g of fresh xoconostle peel with three replications.
The sweetener did not affect dehydration time of convective heat. The sweetened
lyophilized xoconostle had lower TP and AA than unsweetened xoconostle. The
sensorial analysis showed that lyophilized xoconostle sweetened with neotame
(aqueous solution 32 mg L-1) has acceptable flavor and appearance.

Golden berry (Physalis peruviana L.) is an indeterminate habit plant,
during its vegetative growth nitrogen is the nutrient most demanded and usually
absorbs it as nitrate. A combination of NH4+ y NO3-, where NH4+ is lower than
or equal to 50 % of total nitrogen increases plant growth, only under certain
circumstances and this beneficial effect varies across cuhivars, but the
response to ammonium in golden berry is not known. Therefore, the objective of
this study was to evaluate the morphologic response, fruit yield and quality of
Physalis peruviana L. plants in two year-old plants, (re-sprout) and in new
plants derived from seed, to the joint application of NH4+ and NO3-.
Experiments were carried out in a greenhouse with a completely randomized
design and treatments of the first experiment were the result of combining the
ratio NH4+/NO3- (0:100, 25:75 and 50:50), and sprout vigor (low, medium and
high). In a second experiment new plants derived from seeds were used and with
the same ratios NH4+/NO3- used in the first experiment. Results were analyzed
using ANOVA and treatment means were compared with the Tukey’s test (p <=
0.05). In re-sprouting plants, the highest values of final height and stem
diameter were obtained in plants with high vigor and with the application of 25
% of NH4+ (p <= 0.05), whereas the highest yield was obtained in plants with
high and medium vigor, and with 50 and 25 % of NH4+ (p <= 0.05). Neither
NH4+/NO3- ratio in the nutrient solution nor the vigor of the re-sprouts affected
the concentration of soluble solids or shelf life of the fruits. In plants from
seeds there was also not effect of the NH4+/NO3- ratio on plant height, but
with 50 % of NH4+ the diameter of stem increased. The higher yields were
obtained in plants treated with the ratio 50/50, and the concentration of
soluble solids in fruits did not show a clear effect on the ratio NH4+/NO3-,
although at 119 d after transplanting the greatest value in fruits of plants
treated only with nitrate (0/100) (p <= 0.05) was reached. Thus, the
combined application of ammonium and nitrate increases yield but reduces
soluble solids in fruit and shelf life and vigor of re-sprouts is neither
determinant nor consistent on yield.

Background: gastrointestinal parasitism is an important limitation for
sheep production in Cuba. This situation is worsened by the lack of an
effective parasite control strategy. Objective: to assess whether selective and
strategic treatments could help achieve a level of control of nematodes similar
to systematic drenchings. Methods: an experimental group of 73 Pelibuey ewes
was divided into four groups: 1) the Epizoo group (Epizootiological drenching
schedule) was dewormed at lambing in the middle of the dry season and at
weaning; 2) the FAMACHA (c) group was treated according to the color of ocular
mucosa as indicative of anemia (Categories 4 and 5 of the FAMACHA (c) color
chart); 3) the Chemical group was drenched every three months; and 4) the
control group, in which animals remained untreated unless fecal egg count (FEC)
was higher than 1500 eggs per gram of feces or the packed cell volume (PCV) was
lower than 15%. FECs, body scorings (BCS), hematocrits and color of ocular
mucosa (COM) were evaluated monthly. Results: the control group showed the
highest FEC and the lowest PCV. We also observed similar levels of FEC and body
condition (BCS) in the Epizoo, FAMACHA (c) and Chemical groups. The PCV in
FAMACHA (c) group was the highest, while no differences were found between the
other two groups. Hematocrit had a strong negative correlation (-0.41) with
FEC. The FAMACHA (c) method allowed a dramatic decrease in anthelmintic use.
Conclusions: the obtained results suggest that FAMACHA (c) method could be
incorporated as part of an effective parasite control strategy in sheep.

Because one of the main problems that Enterolobium cyclocarpum faces in the
planting site is the presence of weeds, to grow plants presenting appropriate characteristics
that enable them to overcome these adverse conditions during reforestation
appears as necessary. Therefore, after evaluating the responses of various
morphological and physiological indicators, and a quality test experiment, the
effects of three top pruning intensities (no pruning, 25 % and 50 % pruning)
and three fertilization regimes (traditional, exponential and conventional)
were studied during nursery production. This approach was made based on the
fact that top pruning and fertilization in the nursery are cultural practices
that improve seedling quality as long as the pruning intensity and
fertilization regime are appropriate. There was no synergy between the two
practices; however, each factor influenced independently on the indicators
evaluated. Top pruning at 25 % and 50 % did not improve the characteristics of
E. cyclocarpum. However, the nutrient supply in a conventional way had a
favorable effect when compared with other fertilization regimes. The results
provided by the quality test established that conventional fertilization allows
plants to perform satisfactorily when nutrient availability is limited.

A study was conducted to examine the responses of microbial activity and
nitrogen (N) transformations along an altitudinal gradient. The gradient was
divided into three parts. Three areas were sampled: upper part (UP): coniferous
forest, corn field, and abandoned corn field; middle part (MP): tropical cloud
forest, grassland, and corn field (COL); and lower part (LP): tropical
deciduous forest and sugarcane. The results showed that soil microbial biomass
carbon (C) and basal respiration were significantly higher in MP and UP than in
LP, whereas the microbial quotient (C-mic/C-org) was higher in LP and MP than
in UP. The metabolic quotient (qCO(2)) was similar among gradient parts
evaluated. Net N mineralization, ammonification, and nitrification rates were
higher in UP than MP and LP. We found that in UP, the forest conversion to
cropland resulted in no significant differences in microbial activity and N
transformation rates between land uses. In MP, microbial biomass C,
ammonification, and net N mineralization rates decreased significantly with
conversion to cropland, but C-mic/C-org and nitrification were higher in COL.
Basal respiration and qCO(2) were significantly lower in COL when compared with
other land uses. In LP, lower microbial biomass C, C-mic/C-org, and
nitrification rates but higher ammonification and net N mineralization rates
were observed in tropical deciduous forest than in sugarcane. No significant differences
in basal respiration and qCO(2) were found between uses of LP. Clearly, then,
soil organic C is not equally accessible to the microbial community along the
gradient studied. Copyright (c) 2012 John Wiley & Sons, Ltd.

Biosynthesis of silver nanoparticles (AgNPs) was achieved using extract of
Chenopodium ambrosioides as a reducer and coating agent at room temperature (25
degrees C). Two molar solutions of AgNO3 (1mM and 10mM) and five extract
volumes (0.5, 1, 2, 3, and 5 mL) were used to assess quantity, shape, and size
of the particles. The UV-Vis spectra gave surface plasmon resonance at 434-436
nm of the NPs synthesized with AgNO3 10mM and all extract volumes tested,
showing a direct relationship between extract volumes and quantity of particles
formed. In contrast, the concentration of silver ions was related negatively to
particle size. The smallest (4.9 +/- 3.4 nm) particles were obtained with 1mL
of extract in AgNO3 10mM and the larger amount of particles were obtained with
2mL and 5mL of extract. TEM study indicated that the particles were
polycrystalline and randomly oriented with a silver structure face centered
cubic (fcc) and fourier transform infrared spectroscopy (FTIR) indicated that
disappearance of the -OH group band after bioreduction evidences its role in
reducing silver ions.

In recent years numerous studies have been carried out to incorporate plant
growth promoter micro-organisms in agricultural production. However, there is
little information about studies on the effects of these micro-organisms on
forest species, especially of arid zones. The present work is focused on
evaluating the effect of inoculation of Bacillus spp., Trichoderma spp., Glomus
intraradices and halophyte rhizobacteria on the germination of seeds of
Echinocactus platyacanthus, a species native to Mexican semi-desert areas.
Results show that microorganisms play an important role in promoting the
germination process of Echinocactus seeds, the germination promotion by
micro-organisms being higher when the seeds are washed.

The effects of zinc and cadmium on the growth, mineral composition (P, K,
Ca, Mg, Fe, Zn, Mn, and Cu), and metal accumulation by lupine (bluebonnet, Lupinus
uncinatus Schldl.) were investigated in a hydroponics experiment. Plants were
exposed to increasing concentrations of Zn (0, 30, 40, and 50 mu M) and Cd (0,
3, 4, and 5 mu M) for 1 week. The species showed different patterns of metal
accumulation and distribution in the plant parts, suggesting different
mechanisms of metal tolerance for each metal. At the highest doses of Zn and
Cd, the amounts of metals accumulated in roots, stems, and leaves were 1,289,
1,918, and 1,132 mg kg(-1) dry matter and 2,467, 227, and 164 mg kg(-1) dry
matter, respectively. The shoot:root Zn ratios obtained for 50, 40, and 30 mu M
treatments were 2.36:1, 2.28:1, and 2.32:1, respectively, whereas the ratio in
case of Cd remained < 1 for the three Cd treatments. No significant effect
on plant dry biomass was observed in either of the cases. Significant changes
in plant mineral composition occurred, however, concentrations were generally
above the deficiency levels. This suggests that this species may tolerate Cd
without its hyperaccumulation and shows exclusion mechanism of Cd tolerance.

Pinus johannis M.-F. Robert-Passini is an endemic pinion nut pine of Mexico
that grows in small populations. The objective of this study was to estimate
the level of genetic diversity and degree of differentiation among populations
in the natural distribution of P johannis. Mature strobili were collected from
130 tree of four populations. The genotype of each tree was determined in a
sample of six megagametophytes, and nine enzyme systems with 16 loci were
analyzed. In the four populations the number of alleles varied from 31 to 35.
The average number of alleles per locus was 2.1, and the average percentage of
polymorphic loci was 88 %. Average heterozygosity was 0.231, and expected
average heterozygosity was 0.245. A deficit of heterozygous individuals (F-IS =
0.116 and F-IT = 0.176) was found in the four populations together and in each
of them. The genetic differentiation among populations was moderate (F-ST =
0.062). Genetic diversity of P johannis was high with a moderate level of
differentiation among populations.

Objective.To identify the risk of brucellosis in the state of Tlaxcala,
Mexico. Materials and methods.A diagnosis of social type was conducted in the
municipalities of Huamantla, Ixtenco and Teacalco, located in the eastern
region of the state.The seroprevalence of brucellosis in goats and humans was
determined. Results. 46.9% of producers know the programs of vaccination
against brucellosis; 19.7% apply the vaccine and 80.3% do not apply the
vaccine. Huamantla had the highest seroprevalence of animal brucellosis in
66.8%; San Jose Teacalco distributes unpasteurized cheeses to a distance of 270
km, increasing the risk of infection with brucellosis. Ixtenco recorded the
highest prevalence of brucellosis in humans, with 1.51%.Conclusion.The
municipalities studied present risks of infection and spread of brucellosis.

Globally, remnant fragments of forests represent the main carbon reservoir
of terrestrial ecosystems, but they suffer strong degradation due to
uncontrolled wood extraction mainly by tree cut for household fuel use and
charcoal production. The present study evaluates the degradation caused by wood
extraction on carbon pools and soil nutrient dynamics in temperate forests
distributed in remnant fragments located in central Mexico. Four sites with
different intensity of wood extraction were chosen for measuring carbon pools
and nutrient fluxes during two years. Both, aboveground carbon biomass and soil
organic carbon values decreased with the intensity of forest degradation. The
degraded forest (DF) showed total carbon content 55 % lower than that shown by
the seminatural forest (SF). Additionally, litterfall production was reduced in
DF as compared to SF; the decomposition rate of standing litter was higher in
the latter site. As a consequence, DF had lower organic matter inputs to the
soil than that presented by SF. Soil extractable ammonium and microbial
biomass-carbon and -nitrogen were lower in DF than in SF. It was concluded that
the uncontrolled wood extraction in these remnants of temperate forest in
Mexico significantly reduced the carbon pools, carbon and nutrient fluxes
through litterfall and consequently, the soil nutrient dynamics were disrupted.

Background: In sheep production systems based on grazing, gastrointestinal
nematodes (GIN) are one of the main problems faced by farmers. The occurrence
of anthelmintic resistance in GIN has endangered the productive activity of
sheep, so that one alternative has been through the selection of sheep. The
selection programs are based on evaluation of parasitism by measuring the fecal
egg counts (FEC) of GIN due to the high correlation between the FEC and worm burdens.
The identification of resistant and susceptible lambs requires knowing the FEC
after the infection. The aim of this research was to determine the intra-breed
variability on FEC of GIN in Katahdin x Pelibuey grazing sheep. Materials,
Methods & Results: The experiment was conducted in Tabasco, Mexico in a
warm humid climate. The study was carried out in three stages: in stage I, the
FEC was recorded in newly weaned lambs experimental infected with 1600
infective larvae (L 3) of Haemonchus contortus and Cooperia curticei (85% and
15% respectively). Twenty lambs were drenched with albendazole and 20 more
lambs were considered as control without any anthelmintic treatment. In stage
II acquired resistance was determined in the same animal group after a break
period following the same treatments. In stage III new lambs were introduced to
paddocks and the FEC was recorded in their first infection. Every 15 days fecal
sample, live weight and blood samples were taken to determine FEC, daily gain
weight and packed cell volume. Data were analyzed with a model of repeated
measures over time. In order to establish the level of anti-parasitic
resistance in the lambs, a categorization of the lambs according to their FEC
was performed based on the EPG mean and standard deviation. Subsequently
another statistical analysis was performed by category to determine the EPG,
PCV and DWG values per group. In primary infection, both lambs treated with
albendazole and control group reached a maximum elimination at 32 days post-infection
(4202 +/- 558 EPG mean). In the second natural infection the same lambs had
less FEC (989 +/- 378 EPG), while in the newly weaned lambs of the third stage
the FEC was rapidly increasing at 18 days (2950 +/- 471). Derived from the
categorization process of the lambs, it was observed that resistance animals
had lower FEC (282 +/- 197.5) and higher PCV (27.9 +/- 2.5 %) than the
susceptible animals (5424 +/- 3790 FEC and 25.19 +/- 1.95 %, respectively).
However, weight gains were similar among the groups (0.04 +/- 0.05 kg) and
packed cell volume was similar between resistant and intermediate group. A
negative correlation (r = -0.30) was obtained between PCV and FEC due to H.
contortus population was abundant. Discussion: During the pre-patent period, no
paddock contamination occurred; so, no lamb re-infections were expected. This
fact can explain why the subsequent reduction in the larvae population occurred
after 35 days infection. A similar behavior in the FEC was observed in single
infections in other studies. It is important to remark that in the second stage
the same experimental flock after deworming with levamisole showed evidence of
acquired resistance against GIN after being exposed for second time to the
infection. In the third stage, the increasing in the FEC and reduction of the
PCV values in the flock required an urgent anthelmintic treatment; because six
animals had shown a PCV ranged between 17 and 19%; so it was decided to
terminate the experiment. It is concluded a low percentage of lambs showed the
characteristics of resistance during the first infection, selection of animals
with resistance to gastrointestinal parasitic nematodes is possible and it
should be investigated in depth in further studies as a possible potential tool
of parasitic control.

The psyllid Trioza aguacate Hollis & Martin (Hemiptera: Triozidae)
causes deformation of leaves and young shoots of avocado. In recent years,
population densities of this pest in avocado orchards have increased. The
objectives of this study were to determine seasonal fluctuations of the
populations of eggs, nymphs, and adults of T. aguacate, how these fluctuations
are related to the incidence of avocado vegetative shoots, temperature and
rainfall at 3 different altitudes in Michoacan, Mexico, i.e., 2,130 m, 1,860 m
and 1,293 m. In addition, we attempted to determine the spatial distributions
of nymphs and adults found on avocado vegetative shoots. We sampled the
populations of adult and immature T. aguacate every 20 days from Jan 2012 to
Jul 2013. To estimate population densities, 9 trees were selected in each
orchard, and the trees were distributed in the form of a cross. From each
replicate of trees, 4 shoots were randomly collected, and the eggs and nymphs
were counted on them. Adults counts were obtained from yellow traps established
at the 4 cardinal points in each tree. During the same period, young vegetative
shoots, temperature and rainfall were recorded. The results showed that this
psyllid was not present at all in the orchard located at the low altitude level
of 1,293 m. The psyllid was present at the medium altitude site from Jan to
Jun, and from Dec to Jun at the high altitude site. All of the development
stages were most abundant from Mar to May, when avocado vegetative shoots were
most abundant in both years. The abundance of eggs and nymphs showed a positive
relationship with young vegetative shoots, a negative relationship with
rainfall, and the eggs showed a positive relationship with temperature. The
incidence of adults was strongly related with spring budding, but not
significantly correlated with temperature. Both nymphs and adults had an
aggregated spatial distribution.

In situ ruminal digestibility of four low quality forages (corn stover,
sugarcane bagasse, wheat straw and alfalfa hay control) was evaluated with the
addition of enzymatic extract of Cellulomonas flavigena. The enzyme extract (42
IU xylanases ml(-1)) was sprinkled over the forages at 1 ml g(-1) 24h before
incubation. Samples were incubated in the rumen of a Holstein cow fitted with a
ruminal cannula for 3, 6, 9, 12, 24, 48 and 72h. There were positive effects of
the enzyme (P<0.05) on forage DM digestibility at 24 and 48 h of incubation.
However, there was no variation in the NDF digestion owing to enzyme or the
forage source. In contrast, ADF degradation showed differences (P<0.05)
among forages in all incubation times, indicating that the enzyme acted on the
hemicellulose and fodder containing different cell wall percentages. Results
indicate that Cellulomonas flavigena enzymatic extract improves in situ
degradation of DM and ADF in low quality forages

Caesalpinia gaumeri Greenm is an important timber species in the tropical
deciduous forest in southeast Mexico. The trunks of this species are used as
posts in rural construction. In this study we investigated which morphological
and environmental factors influence annual diameter growth, in order to
establish the best turnover period. Diameter growth in 32 trees located in four
diameter categories were evaluated and classified according to quality and
sunlight incidence on the crowns of the trees. The study lasted 22 months and
the diameter at breast height was measured and recorded bi-monthly. The results
indicate that Average Growth Rate (AGR) increased from the smallest to the
largest diameter categories, from the damaged to the healthy crown qualities
and from intermediate to total incidences of sunlight. Highest AGR was observed
in diameter categories of 12.50 to 22.49 cm in trees with symmetrical crown
quality and the crown under full sunlight. The cumulative AGR was highly
significant (P < 0.001) and positively correlated (r = 0.94) with the
precipitation. Good growth in diameter for C. gaumeri requires a combination of
bigger stem diameter, healthy and symmetric crown, full incidence of sunlight
on the crown and a rainy season.

Nineteen species of seed-beetles belonging to the subfamily Bruchinae
(Coleoptera, Chrysomelidae) were collected in Xinjiang, China. Of these, the following
four were new records for China: Bruchus affinis Frolich, 1799, B. atomarius
L., 1761, B. loti Paykull, 1800 and Kytorhinus kergoati Delobel & Legalov,
2009. We provide an annotated checklist, illustrations and a key to the 19
species.

Mucilage from stems of cactus (Opuntia ficus-indica) “Milpa Alta” (Mm) and
“Toluca” (Mt), in a single ingredient condition and in mixture with gelatin and
beeswax, was used to prepare biopolymeric films, which were assessed in terms
of microscopic morphology, thickness, transparency, tensile strength, and
permeability to water vapor, O-2, and CO2. Films based on Mm were thinner, with
higher transparency, and higher tensile strength than those of Mt, but they had
similar barrier properties to water vapor, O-2, and CO2. The addition of
gelatin did not affect thickness and transparency of such films, but caused
modification of the microscopic morphology, the mechanical strength, and the
barrier properties to gases and water vapor. Furthermore, the addition of
beeswax promoted the formation of aggregates in the microscopic morphology of
films and these acquired smaller thickness, higher tensile strength, and higher
barrier properties to O-2, CO2, and water vapor, which may give them better
potential to be used in the postharvest conservation area of horticultural
products, although they were less transparent.

Rivers are vital units in the functioning of the watersheds that, due to
the transportation and circulation of water, allow the existence of life. They
are of great ecological and environmental value because of their influence on
other ecosystems as well as the benefits they give to humankind, not only in
the consumption for irrigation but also in the use in the agricultural and
industrial areas. However, almost all the rivers in Mexico show a certain type
of deterioration. About 70 % of the aquatic systems shows contamination which
diminishes the health of these ecosystems. The objective of this work is to
propose that the riparian vegetation should be included in the making of the
new general law of water because its influence on the maintenance and
rehabilitation of the ecological state of rivers is fundamental. It has been
suggested a new law that contains a section of environmental protection which
includes the riparian vegetation as a key element to protect, preserve, and
restore rivers. Likewise, the boundaries of this vegetation should be according
to the natural conditions of flooding in the bed of the river, with a
once-in-every eight years-frequency, according to the variability of flow. In
addition, its handling must consider the reforestation and maintenance of
native vegetation species in each region.

In situ conservation of genetic diversity in maize (Zea mays L.) has been
made for years by traditional farmers, through planting native populations, as
is the case of the Jala landrace, whose preservation is threatened by urban
growth and natural factors. The distinctive characteristics of this landrace,
such as plant height and ear length, have become dimibished. The number of
farmers who grow in situ population of the Jala landrace is low, and seed of
this landrace is often exchanged among them. For these reasons, it is relevant
to assess whether or not there is phenotypic variation among current, conserved
populations of the Jala landrace in Jala, Nayarit, Mexico, its place of origin
and primary distribution. In situ morphological characterization of 18 Jala
landrace populations and seven controls were evaluated in 2010 using a 5 x 5
Lattice design with two replications, at three environments within the Jala
Valley. With the averages of variables through environments, a combined
analysis of variance, Tukey’s mean comparison, principal component analysis
(PCA) and cluster analysis (ADC) were performed. PCA defined that the most
influential variables for explaining the observed variation were ear length,
plant height and cob height. ACD defined three groups of populations, in which
there was greater phenotypic similarity with most of the current populations.
It is concluded that in the Jala maize landrace there is low phenotypic
variation among current in situ conserved populations, with a presumably
reduced and common genetic base.

The pepper (Capsicum spp.) weevil (Anthonomus eugenii Cano) is the
principal pepper pest in America, and its management requires efficient
monitoring techniques. The host volatile compounds could be used for this
purpose. In this research the attraction of A. eugenii adults towards an
individual compound and 12 mixtures of synthetic volatile compounds (identified
previously in Capsicum spp.) was evaluated, the effect of three isomers
[(Z)-beta-ocimene, (E)-beta-ocimene, and D-limonene] was determined in the
weevil response, and the best mixture of host volatiles was evaluated, as well
as their combination with the A. eugenii aggregation pheromone and the
pheromone alone. The insect’s response was evaluated through pairwise choice
experiments, carried out in a Y-type olfactometer, with two treatments. The
proportions of insects respondig to each treatment were compared with the
binomial test. Results showed that the mixture of (Z)-beta-ocimene, D-limonene
and 2-isobutyl-3-methoxypyrazine attracted (p <= 0.01) A. eugenii adults of
both sexes. The (Z)-3-hexenyl acetate and the terpinolene, added individually
to the prior combination, increased the response of females (p <= 0.05) and
males (p <= 0.01), respectively. The inclusion of (E)-beta-ocimene as
principal compound, in the same mixture, increased the response by males (p
<= 0.05) and the exclusion of D-limonene did not decrease the effectiveness
of the remaining combination. In the final experiments, males had a greater
response to the mixture of host volatile compounds (p <= 0.05) and to its
combination with the A. eugenii aggregation pheromone (p <= 0.01) than to
the pheromone by itself; in contrast, females did not show a differentiation in
their choice. The research allowed selecting pepper volatile compounds with
potential to attract A. eugenii adults.

Remote sensors combined with geospatial analytical methods provide
important tools for measuring forest biophysical variables at a lower cost and
at broader spatial and temporal scales than traditional forest inventories. The
objective of this study was to analyze the relationship between data of the
National Inventory of Forest and Soils (INFyS) of Mexico and spectral data from
images of the SPOT platform for spatial estimation of basal area, timber volume
and overlapping tree cover in the temperate and mesophyll forests of Hidalgo,
Mexico. Four approaches to the analysis were used to generate models that
describe the inventory and the distribution of the variables of interest: 1)
multiple linear regression, 2) K-nearest neighbor (K-nn), 3) ratio and
regression estimators, and 4) traditional forest inventory. The estimations
derived from the first three methods are within the confidence interval of 95 %
of the traditional forest inventory, and the values derived from ratio and
regression estimators produced narrower confidence intervals. The analysis of
the results indicate significant correlation between the INFyS data and the
spectral bands of the SPOT satellite, particularly with the green, near
infrared and mid infrared bands, as well as with the indexes and simple ratios
based on these bands.

In Central America, the traditional cropping system milpa de alio (summer
season) and tornamilpa (winter season) were compared over 3 yr (2007-2009). Our
experimental objectives were to measure the performance fa maize (Zea mays L.)
velvet bean [Mucuna pruriens (L.) DC. subsp. utilis (Wight) Burck] mid milpa
system throughout the summer and winter cultivation, to detect any problems
associated with velvet bean use, and to determine the contribution of this
tropical legume to soil fertility and maize productivity. In each crop season
(separated in space and time) we used a completely randomized design with a 2 x
2 factorial arrangement of treatments with five repetitions each: without
velvet bean and without fertilizer ( V F), with velvet bean and without fertilizer
(+V-F), without velvet bean and with fertilizer (-V+F), and with velvet bean
and with fertilizer (+V+F). Results showed that in the winter milpas the
presence of velvet bean significantly increased the soil pH, organic matter
content, total N, and decreased soil bulk density. In both cycles (winter and
summer), treatment with velvet bean (+V) produced higher grain yield, while the
treatment without velvet bean (-V) had a lower production. We concluded that
the use of velvet bean in the winter milpa contributed to the restoration of
soil fertility and increased yield maize in agricultural systems of the
small-holder farmers based on low external input.

The objective was evaluating the response to mineral (230-0-300 and 230-0-0
g NPK tree(-1)) and organic: vermicompost, bokashi and chicken manure (5 and 10
t ha(-1)) fertilizers in soil nutrimental content (pH, MO, macro and
micronutriments), trunk diameter, flowering, and yield of three mango
cultivars: “Manila”, “Tommy Atkins”, and “Ataulfo”. For soil variables were
design completely random and other variables a split-plot in completely random.
Differences between contents of N, K, Ca, Cu and Zn were showed in soil.
Differences were showed between cultivars in trunk diameter. Flowering showed
differences among cultivars and fertilizers. Regarding yield in 2010, only
“Tommy Atkins” fruits were harvested, showing differences between fertilizers
and control. In 2011, were differences among cultivars and fertilizers, chicken
manure and mineral fertilizers outperformed the control. In 2012, “Tommy
Atkins” outperformed “Ataulfo”. It is concluded that chicken manure 10 t
ha(-1), were similar to nitrogen doses on soil contents of N, K, Cu and Zn;
fertilizer do not have influence in the trunk diameter; on flowering and yield,
bokashi and chicken manure 10 t ha(-1), were similar to nitrogen doses.

The objective of this study was to evaluate, animal behavior, quality, and
composition of the diet selected by cattle grazing on stargrass (Cynodon
plectostachyus) in monoculture and associated with Leucaena leucocephala (Lam.)
De Wit. and Guazuma ulmifolia (Lam.) in the dry tropics of Chiapas, Mexico. For
this purpose, animals’ behavior was observed for 24 h. It was estimated quality
as well as botanical composition of the diet selected. Data wereanalyzed by
variance with a completely random design. Comparison of means was carried out
using Tukey’s test. Non significant differences were reported for the animal
behavior data (P>0.05). In the associated grassland, it was found that more
time was dedicated to browsing during the dry season (P<0.05). The best diet
selected, in terms of crude protein was found in the associated grassland
(P<0.001), for both seasons. In this grassland, woody plants were found in
the diet selected during both seasons. Nevertheless, more woody species
contributed to the diet during the dry as compared to the rainy season (52.1
versus 26.9 %, respectively).

Ectomycorrhizal (ECM) fungal communities have been relatively poorly
documented in neotropical forests. We analyzed the structure and diversity of
the ECM resistant propagules present in the soil of Mexican neotropical forests
dominated by Pinus montezumae. Soil samples were collected under mature P.
montezumae, and microcosms were set up with bioassayed seedlings. The ECM
propagules were formed by relatively few taxa that were evenly distributed
across the sampled area. Some taxa, such as Rhizopogon spp. and Atheliaceae
sp., formed an extensive mycelial system, which is likely to confer them with
an advantage for seedling colonization. We also compared the species
composition of the ECM propagules with the ECM communities previously assessed
on the roots of seedlings and adult trees. They were represented by different
taxa, although similarity analyses did not detect differences in species
occurrence. Only two taxa, belonging to the Atheliaceae family, were shared
between field and bioassayed seedlings, whereas 12 taxa were common to field
seedlings and adult trees. The lower similarity between bioassayed and field
seedlings suggests that fungal taxa found as resistant propagules are not
active in mycelial networks in field conditions and that mycorrhizal network-mediated
colonization may be prevalent in this neotropical forest. (C) 2014 The
Mycological Society of Japan. Published by Elsevier B.V. All rights reserved.

Within the diversity of maize (Zea mays L.) in Mexico, one of the most
interesting genetic groups is the Mexican Pyramidal Complex grown in the
Central highlands of the country. This study assessed the morphological and
agronomic diversity in a large sample of populations of the seven races of
maize most commonly cultivated in the highlands of Central Mexico (Arrocillo
Amarillo, Chalqueno, Conic, Elotes Conicos, Cacahuacintle, Palomero Toluqueno
and Purepecha), and to register information of characteristics that describe
the prevailing variation of the races under study. Field experiments were
established during the 2010 Spring-Summer agricultural season with 119
representative accessions of the aforementioned races of maize, at Ciudad
Serdan and San Mateo Capultitlan, Puebla, and at Montecillo, State of Mexico,
using an 11 x 11 simple lattice experimental design. Thirty-two quantitative
traits were recorded and submitted to analysis of variance, and 13 of those traits
were selected based on their repeatability and correlation coefficients, for
applying multivariate analyses. Analysis of variance showed highly significant
differences among genotypes for all the analyzed traits. The dispersion of
accessions ended up as a continuum distributed throughout the Cartesian plane
formed by the first two principal components, mainly influenced by traits
related to ear and kernel size (ear length, kernel width and thickness, and the
ratio kernel width/kernel length), as well as days to female flowering and
number of leaves above the ear. The traits less affected by the environment
were the most appropriate ones for grouping the accessions. Results of this
study confirmed the grouping of the accessions of previously described races,
as well as the interrelations among them as reported in previous studies;
however, our result are more precise than the former studies in defining the
groups and the interrelationships among the races because of the large sample
sizes used.

In Mexico there is a broad diversity of maize. To design schemes of genetic
improvement and germplasm conservation, this diversity must first be assessed.
In this context, an analysis of microsatellites was conducted to estimate the
degree of variation and to analyze the structure and genetic diversity of seven
maize (Zea mays L) landraces from the High Central Valleys of Mexico (Arrocillo
Amarillo, Cacahuacintle, Chalquefio, Conico, Elotes Conicos, Palomero
Toluquerio and Purepecha) as well as the teosinte races Chalco [Zea mays ssp.
mexicana (Schrader) Iltis] and Balsas [Zea mays ssp. parviglumis (Iltis and
Doebley)]. Seed from 107 accessions kept in Mexican germplasm banks was used.
We analyzed 31 SSR loci to estimate genetic variation based on the number of
alleles per locus, proportion of polymorphic loci and index of expected
heterozygosity, and genetic structure using Wright F statistics. Races were
grouped based on principal component and cluster analyses. A total of 636
alleles were identified, averaging 20.52 alleles per locus, 92.75% of which
were polymorphic loci. Also found were 100 alleles exclusive of some of the
studied populations. Occurrence of these alleles was low, representing 16% of
the total alleles found. It was determined that 76.3% of the genetic diversity
of the cultivated landraces of the High Valleys of Mexico resides within
populations and the remaining 23.7% is between populations. Well-defined groups
of the races Cacahuacintle and Purepecha, as well as two groups of the
Chalqueno race, were observed. The Purepecha race formed a compact group
separate from the rest, while a large sample of the Elotes Conicos race group
was placed intermediately among one of the groups of the Chalqueno race.

Organic fertilizers provide an important contribution of organic matter
that modifies the physical, chemical and microbiological characteristics of the
soil. To determine the impact of solid and liquid fertilizers on cultures of
Alpinia purpurata, the supply of organic C, total N and available P of five
organic fertilizers, the population density of phosphate solubilizing bacteria
(PSB), the indigenous arbuscular mycorrhizal fungi (AMP), and the plant
responses were evaluated, at 365 days, on a Fluvisol soil. The treatments were
compost, vermicompost, fermented manure, Bokashi and liquid humus, at doses of
6Mg.ha(-1) of solid fertilizers, and 60 l.ha(-1) of liquid fertilizers, and
compared with chemical fertilizer (150-50-250) and a control. The organic
fertilizers applied showed that after a year, the C, N and P concentrations in
the soil maintained acceptable nutritional levels for production. Organic
fertilizers increased five times the population density of PSB and 12% the
total colonization by AMF, promoting a higher P availability for the plants,
improving the production of total biomass and flower quality, fermented manure
and compost standing out in production.

The purpose of this study was to determine how feeding sheep coffee pulp
affects carcass characteristics and what changes occur in physicochemical,
antioxidant capacity and oxidation of the meat during refrigerated storage. The
experiment was carried out in 15 Blackbelly lambs weighing an average 22.86 +/-
0.76kg. The animals were assigned to three treatments: T0=control diet, T1=diet
with 8% coffee pulp, and T2=diet with 16% coffee pulp. After fattening for 56
days, the sheep were slaughtered and the carcasses assessed. The inclusion of
16% coffee pulp in the diet increased carcass dressing from 48.19 to 50.83% and
decreased the amount of fat in rumen and intestines from 3.43 to 2.53%
(P<0.05). The inclusion of coffee pulp in the diet did not alter the amount
of crude protein or fat in meat or its oxidation and antioxidant capacity
during refrigerated storage. However, the inclusion of coffee pulp in the diet
decreased fat in the rumen and intestines, and thus increased the amount of
usable meat.

A list of the diversity of cacti in the arid and semi-arid zone of Durango,
Mexico is presented The zone includes 16 municipalities that belong to the
Region of Chihuahua Desert. Field trips were made for specimen collection and
registration in each municipality. The best represented genera are Coryphantha,
Opuntia, Echinocereus and Mammillaria. The globose and cylindrical growth forms
are the most common ones in the region. The municipalities with highest
diversity were Mapimi, Tlahualilo and Nazas, while those with the largest
numbers of species at risk were PeliOn Blanco, Mapimi, Tlahualilo and Nazas.

The aim of this research was to identify wild plant species applicable for
remediation of mine tailings in arid soils. Plants growing on two mine tailings
were identified and evaluated for their potential use in phytoremediation based
on the concentration of potentially toxic elements (PTEs) in roots and shoots,
bioconcentration (BCF) and translocation factors (TF). Total, water-soluble and
DTPA-extractable concentrations of Pb, Cd, Zn, Cu, Co and Ni in rhizospheric
and bulk soil were determined. Twelve species can grow on mine tailings, accumulate
PTEs concentrations above the commonly accepted phytotoxicity levels, and are
suitable for establishing a vegetation cover on barren mine tailings in the
Zimapan region. Pteridium sp. is suitable for Zn and Cd phytostabilization.
Aster gymnocephalus is a potential phytoextractor for Zn, Cd, Pb and Cu;
Gnaphalium sp. for Cu and Crotalaria pumila for Zn. The species play different
roles according to the specific conditions where they are growing at one site
behaving as a PTEs accumulator and at another as a stabilizer. For this reason
and due to the lack of a unified approach for calculation and interpretation of
bioaccumulation factors, only considering BCF and TF may be not practical in
all cases.

The objective of this study was to evaluate the in vitro effects of slow
release urea on gas production and degradation of dry matter and neutral
detergent fiber for alfalfa hay, oat straw and corn silage and Stover. The
addition of the slow release urea in alfalfa and oat cultures did not improve
the degradation of these substrates. However in forages with low content of
crude protein, e.g. corn silage and stover, the addition of slow-release urea
alone or in combination with urea resulted in a significant increase in
degradation and gas production.

Mexico is one of the largest users of N fertilizer in the world, and the
2nd largest user in Latin America after Brazil. Across large areas of Mexico, N
fertilizers are being over-applied, resulting in lower N use efficiency.
Mexico’s greenhouse gas (GHG) inventory (in CO2 equivalents) reports that
agricultural production contributes to about 12% of the country’s emissions,
with N2O-N emissions from fertilizer contributing about half of the GHG
emissions from agriculture. Mexico does not have tools that can be used to
assess N fertilizer use and emissions of N2O-N from organic and inorganic
sources. Such tools could be used to help nutrient managers implement
management practices that increase N use efficiencies and reduce N2O-N
emissions. The new Nitrogen Index tier zero tool was used to assess N use
efficiencies and N2O-N emissions in different cropping systems of Mexico.
Mexico’s current GHG inventory for agriculture just multiplies the use of N
fertilizer in the country by 1% to assess national emissions of N2O. When we
tested the new tier zero Nitrogen Index, it performed much better than the
current methodology for calculating Mexico’s N2O emissions, and N2O emissions
predicted by the tool were correlated with observed values (P < 0.01). The N
index tool was closer to measured values than the current method used for
Mexico’s GHG inventory. We propose that this prototype of the Nitrogen Index
tier zero for Mexico can be used to assess the effects of cropping systems and
N management practices on emissions of N2O-N in Mexico to improve the accuracy
of the national inventory of N2O-N emissions in Mexico, which is reported to
the United Nations Framework Convention on Climate Change (UNFCCC).
Additionally, the tool can also be used to assess N management practices to
increase N use efficiency with just a minimal amount of information provided by
the user. Published by Elsevier B.V.

The purpose of the research reported here was to develop a list of plants
utilized by the ancient inhabitants of prehispanic Teotihuacan through the
botanical and ethnobotanical interpretation of archaeobotanical and
iconographic records. The resulting register of useful plants is comprised of
77 taxa, based on published studies and archaeological reports. A Cultural
Significance Index was proposed in order to combine the information from
different sources and evaluate their relative importance. Identified archaeobotanical
remains and their interpretation based on archaeological excavations provide
direct evidence for the use of plants. Representations in ceramics and mural
paintings, along with evidence associated with cultivation or importation of
some species, provide indirect evidence. Maize (Zea mays L.) is characterized
as the most significant cultural species. The uses attributed to taxa reported
from the archaeological record and related species were then consulted in the
Florentine Codex, as well as contemporary ethnobotanical studies, both of which
offer many additional references to the ways in which these plants were
employed. Medicinal uses appear to be the least important at Teotihuacan (eight
taxa); however, according to more recent sources, 57% of the species could have
had medicinal applications. A total of 125 potentially useful plants were
identified from Teotihuacan, based on the ethnobotanical interpretation, and
includes 17 species definitely grown in Teotihuacan and 108 additional
exploited taxa associated with different types of vegetation. Twenty-eight
plants were domesticated in Mexico. This study contributes to an understanding
of the relationship between the inhabitants of Teotihuacan to their local and
regional flora.

New estimators for the parameters of the Gamma distribution are proposed,
which are used for constructing a test a fit for this model based on the ratio
of two variance estimators. The asymptotic null distribution of the test
statistic is also included. (C) 2014 Elsevier B.V. All rights reserved.

Lychee (Litchi chinensis Sonn.) is a fruit originating from China and
Vietnam which is cultivated in México also, and Veracruz is cultivated with “Mauritius”
and “Brewster” cultivars and it is the main state for the national and
international markets. The aim of this research was to evaluate the physical
and chemical characteristics of lychee fruits produced in six orchards located
at the central and northern regions of the state of Veracruz. For this study 4
kg were sampled per each orchard, from which 40 fruits were randomly selected
for quality evaluation. The variables measured were: length, diameter,
firmness, weight of fruit and its components (e.g. pulp, peel and seed), total
soluble solids, titratable acidity, and pericarp color. The “Mauritius” fruits
varied in quality amongst orchards. The Lechuguillas orchard showed the biggest
fruits with 35.1 mm length, 21.2 g of total weight and 16.8 g of pulp weight.
Furthermore, fruits of this site had low acidity, acceptable peel color and
high content of total soluble solids.

The antiproliferative potential of a crude extract from the chayote hybrid
H-837-07-GISeM® and its potential for apoptosis induction were assessed in
leukaemic cell lines and normal mouse bone marrow mononuclear cells (BM-MNCs).
The extract strongly inhibited the proliferation of the P388, J774, and WEHI-3
cell lines (with an IC50 below 1.3 μg·mL−1), reduced cell
viability, and induced apoptotic body production, phosphatidylserine translocation,
and DNA fragmentation. However, the extract had no effect on BM-MNCs. We
postulate that these properties make the extract a good candidate for an
anti-tumour agent for clinical use.

The xoconostle (Opuntia matudae Scheinvar) is a sour fruit, of which the
peel is consumed. It is perishable, but it has a beneficial effect on human
health, as recognized popularly in Mexico. The objective of this study was to
create a snack of dried xoconostle using neotame, an artificial non-caloric
sweetener, to improve flavor. We present (a) a partial chemical
characterization of the fruit (total phenolic content (TP) and antioxidant
activity (AA)), (b) dehydration techniques (heating by convection and
freeze-drying), and (c) sensorial characterization of the final product. The
experimental unit was 40 g of fresh xoconostle peel with three replications.
The sweetener did not affect dehydration time of convective heat. The sweetened
lyophilized xoconostle had lower TP and AA than unsweetened xoconostle. The
sensorial analysis showed that lyophilized xoconostle sweetened with neotame
(aqueous solution 32 mg L-1) has acceptable flavor and appearance.

Interest in ethical aspects associated to product acquisition and
consumption is a growing trend among consumers. In this context, the concept of
“product with ethical attributes” has arisen to refer to products with explicit
social and environmental characteristics. However, one of the factors that most
hinders the purchasing of these products is certainly price. Given the
difficulty of reducing price, the question that arises is the extent to which
other product attributes can attenuate the negative impact of price on
perceived value. We assume that the special benefits associated to this type of
products (ethics, quality and health) are, at a different level, attenuators of
the relationship between price and perceived value. Focusing on Fair Trade
organic coffee, hypotheses are tested regarding survey data from 407 customers.
They were interviewed in an actual purchasing scenario. The models are tested using
conventional Structural Equation Models and the Latent Moderated Structural
Equation method. The results obtained shed some light on a highly generalised
belief that the marketing of these products can only be improved by reducing
their price. However, although a price reduction could be desirable, albeit
complicated in this product category, its effects could be reduced by acting on
other variables such as the ethical aspects, quality and healthiness of this
product category.

In vitro conditions such as low light intensity, the levels of sucrose and
other nutrients, and high relative humidity may cause anatomical and
physiological changes that have negative effects on acclimatization of
regenerated plants. The management of these conditions during in vitro culture
could improve the plant ex vitro performance. The influences of light
intensity, sucrose concentration, the nutritional composition of the culture
medium, and culture container size on in vitro rooting and acclimatization were
evaluated in Capsicum chinense cv. Naranja plants. The size of the culture
container vessel did not affect plant growth. The best responses of the growth
variables tested (plant height, number of leaves, number of roots, dry weight,
and osmotic potential) and of survival and rooting were obtained with a
photosynthetic photon flux density (PPFD) of 28 μmol m−2 s−1 and H medium with
sucrose supplementation at either 1.5% or 3% (w/v). The combination of a PPFD
of 28 μmol m−2 s−1
and H medium with 1.5% sucrose can be used for successful rooting of C.
chinense adventitious shoots, to enhance the performance of the plantlets in
the greenhouse or field and to reduce production costs. The factors studied
during in vitro culture significantly influenced ex vitro growth.

Genome-wide association studies (GWAS) have detected large numbers of
variants associated with complex human traits and diseases. However, the
proportion of variance explained by GWAS-significant single nucleotide polymorphisms
has been usually small. This brought interest in the use of whole-genome
regression (WGR) methods. However, there has been limited research on the
factors that affect prediction accuracy (PA) of WGRs when applied to human data
of distantly related individuals. Here, we examine, using real human genotypes
and simulated phenotypes, how trait complexity, marker-quantitative trait loci
(QTL) linkage disequilibrium (LD), and the model used affect the performance of
WGRs. Our results indicated that the estimated rate of missing heritability is
dependent on the extent of marker-QTL LD. However, this parameter was not
greatly affected by trait complexity. Regarding PA our results indicated that:
(a) under perfect marker-QTL LD WGR can achieve moderately high prediction
accuracy, and with simple genetic architectures variable selection methods
outperform shrinkage procedures and (b) under imperfect marker-QTL LD, variable
selection methods can achieved reasonably good PA with simple or moderately
complex genetic architectures; however, the PA of these methods deteriorated as
trait complexity increases and with highly complex traits variable selection
and shrinkage methods both performed poorly. This was confirmed with an
analysis of human height.

Mexico has one of the largest diversities of pines and ectomycorrhizal
fungi known world-wide. Therefore, describing native ectomycorrizal species
from the country associated with pines is important because of their
biotechnological potential in the forestry and food sectors. Worldwide,
Hebeloma has generally been considered a genus of poisonous ectomycorrhizal
fungi. However, interestingly, in central Mexico there is a complex of
under-studied Hebeloma species which are used as food in large quantities and
have a great economic and social importance. Three edible species of Hebeloma
widely marketed in the country were identified: Hebeloma alpinum, H. mesophaeum
and H. leucosarx with scanning electron microscopy on the basis of different ornamentation
patterns in the spores of these species. Synthesis was carried out by
inoculating two Neotropical pines with sporomes of the three described Hebeloma
species. To achieve this, inoculated pines were kept in greenhouse conditions
during one year. A characteristic morphotype for each fungal species was
observed and it is described here. The first known description of the
morphotype of Hebeloma alpinum with pines is presented. This seminal work gives
a tool to identify the morphotypes produced by the main edible ectomycorrhizal
species of Hebeloma marketed in Mexico, with biotechnological potential to
inoculate pines used in reforestation programmes in Neotropical areas.

Freeze-drying technology is the best dehydration process to preserve
shelf-life and allowing avocado to maintain its sensorial and nutritional
characteristics. The aim of this work was to determine if the freeze-drying and
production condition have an effect on the nutritional quality of the avocado
pulp grown in rain-fed and irrigation orchards. Four treatments were applied:
non-freezedried rain-fed fruits, non-freeze-dried irrigation fruits,
freeze-dried rain-fed fruits and freeze-dried irrigation fruits. Results showed
that the fruit is made up of 71.4%, 16%, and 12.6% pulp, seed and skin, respectively.
The pulp is made up of 71.51%, 19.96%, 2.81%, 0.51% and 1.51% water, lipids,
ashes, crude fiber and protein, respectively. Avocado oil is composed by 61%,
18.8%, 11.6% and 7% oleic, palmitic, linoleic, and palmitoleic fatty acids,
respectively. The freeze-drying decreased the linoleic acid by 1.43 g/100g.
Under rain-fed conditions 4% and 13% less total fat and oleic fatty acid are
produced than in irrigation conditions. We conclude that freeze-dried avocado
pulp shows slight changes in their nutritional quality.

The diversity of races and native populations of maize (Zea mays L.) has
great food, social and economic importance for rural communities in Mexico, and
should to be studied for documentation, conservation and utilization. The aim
of this study was to evaluate the variation in protein, lysine, tryptophan,
crude fiber, ash, oil and starch of grain in a collection of 41 native
populations of maize from the north-central region of Yucatan, Mexico, of the
populations known locally as Nal t’eel, Xmejen nal, T’síit bakal and Xnuuk nal.
The materials were increased in Iguala, Guerrero, in the autumn-winter
2002-2003 cycles. The experimental design was randomized block with two
replications per treatment; an ANOVA was carried out and treatments means were
compared with Tukey’s test. There were significant differences (p≤0.05) in
protein content (9.35 to 12.50 %), lysine (0.27 to 0.39 %), tryptophan (0.08 to
0.13 %), ash (1.12 to 1.83 %), oil (3.37 to 4.52 %), crude fiber (0.72 to 1.65
%) and starch (57.54 to 69.92 %). Besides, the variation patterns are
associated with populations: early Nal t’eel and Xmejen nal had the highest
contents of protein and tryptophan and late T’síit bakal and Xnuuk nal had
lower contents of protein and higher contents of lysine. Six populations of
Xmejen nal, one of Xnuuk nal and one of Nal t’eel were outstanding. Also,
positive and significant correlation (p?0.05) was observed between ash and
lysine (0.99) and tryptophan (0.97) content in the Nal t’eel group. The results
showed high variability in grain composition, useful for breeding programs of
native maize materials and to formulate strategies of in situ conservation of
local collections in the study region.

The thermal and structural properties of starch granules of four maize
genotypes (Palomero Toluqueño native maize, HS-2 commercial hybrid, L3-Q2 M09
experimental hybrid and Cacahuacintle native maize) were studied. By using
adiabatic scanning calorimetry (ASC), the specific heat capacity (cp(T)) of
these samples was obtained. Also, by integration of the area under the cp(T)
curves, the enthalpy for the starch gelatinization was determined, from which
the percentage of gelatinized starch granules was obtained as a function of the
temperature. From the X-ray diffraction patterns of the starch granules, the
degree of crystallinity of the samples was derived. The average size of the
starch granules, for the different maize genotypes, was calculated from the
images obtained by Scanning Electron Microscopy (SEM). We found a correlation
between the enthalpy of gelatinization and the average size of starch granules,
and also between the degree of crystallinity and the average size of the starch
granules.

Cacao (Theobroma cacao L.) represents one of the most important
agricultural crops of the humid Mexican tropics. In the last 10 yr,
approximately 23.000 t of this grain were no longer produced per cycle. The
objective of this study was to identify characteristics and factors that
restrict production in the states of Tabasco and Chiapas. A survey was applied
to obtain information about 184 producers and their plantations by two-stage
sampling. Descriptive statistics were calculated and multilevel models were
adjusted to analyze the information. Results show that there are differences (P
&lt; 0.05) in cacao yield between municipalities (380 kg ha-1+ μojis the
estimated residual for each municipality). Crop productivity levels are higher
in the state of Tabasco than in Chiapas (644 and 344 kg ha-1, respectively).
Incidence of frosty pod rot of cacoa, also known as moniliasis, induced by
Moniliophthora roreri [(Cif) H.C. Evans, Stalpers, Samson &amp; Benny 1978]
is significantly greater (P &lt; 0.05) in the state of Chiapas (60%) than
in Tabasco (48%).Producers who carry out more crop management practices
increase yields and decrease the pathogen’s impact on their plantations.
Results suggest the need to apply differentiated public policies to promote
production within each region or municipality.

Dispersion of mine tailings is the main cause of heavy metal (HM)
contamination in soils in Zimapán, Mexico; however, the extent of this problem
has not been assessed. Therefore, the aims of this study were to determine the
degree of contamination and to assess the influence of mine tailings with
different degrees of weathering on the spatial distribution of HM in soils.
Soil and mine tailing sampling was carried out. The HM concentration was
determined by atomic absorption spectrophotometry; spatial analysis and the size
of the contaminated areas were calculated using GIS software; the mine tailings
were characterized physically, chemically and mineralogically. The results
suggest that all the tailing heaps have contributed to the HM dispersion. High
HM concentrations were founded in soils around mine tailings
(9402 mg kg−1 Pb and 52 mg kg−1 Cd). Surface area
contaminated with Pb and Cd was estimated at 6.2 and 2.7 km2, in urban
soils, respectively.

The objective of this study was to set up optimal parameters for obtaining
industrialized runner bean varieties and to choose those more suitable when
obtaining dehydrated unbroken precooked bean. Taken into consideration
rehydration time and physicochemical and sensorial attributes four varieties of
runner bean, Bayo, Flor de mayo, Flor de junio and Negro, were utilized. In
each one of them sorting, cleaning and wetting were carried out. After that,
they were subjected to a precooking process and dehydration in a tray type
dryer. For each variety and during each process temperature, water content,
relative humidity and contents of ash, protein, carbohydrates and ethereal
extract were determined and records were made of time taken for rehydration and
boiling temperature and sensorial attributes like flavor, appearance, texture
and aroma were obtained from hedonic acceptance tests. All four varieties of
industrialized runner beans showed high content of ash, protein and
carbohydrates. At the hedonic test, four varieties were qualified as “like
slightly”, with no statistically differences between them. Analyzing texture
and flavor, testers preferred Floor de mayo variety, according to appearance
runner bean Bayo and regarding aroma runner bean Negro. Industrialization
process allowed preserving organoleptic quality attributes from each variety as
well as to maintain and increase their nutritional quality.

Globally, remnant fragments of forests represent the main carbon reservoir
of terrestrial ecosystems, but they suffer strong degradation due to
uncontrolled wood extraction mainly by tree cut for household fuel use and
charcoal production. The present study evaluates the degradation caused by wood
extraction on carbon pools and soil nutrient dynamics in temperate forests
distributed in remnant fragments located in central Mexico. Four sites with
different intensity of wood extraction were chosen for measuring carbon pools and
nutrient fuxes during two years. Both, aboveground carbon biomass and soil
organic carbon values decreased with the intensity of forest degradation. The
degraded forest (DF) showed total carbon content 55% lower than that shown by
the seminatural forest (SF). Additionally, litterfall production was reduced in
DF as compared to SF; the decomposition rate of standing litter was higher in
the latter site. As a consequence, DF had lower organic matter inputs to the
soil than that presented by SF. Soil extractable ammonium and microbial
biomass- carbon and -nitrogen were lower in DF than in SF. It was concluded
that the uncontrolled wood extraction in these remnants of temperate forest in
Mexico signifcantly reduced the carbon pools, carbon and nutrient fuxes through
litterfall and consequently, the soil nutrient dynamics were disrupted.

The psyllid Trioza aguacate Hollis & Martin (Hemiptera: Triozidae)
causes deformation of leaves and young shoots of avocado. In recent years,
population densities of this pest in avocado orchards have increased. The objectives
of this study were to determine seasonal fluctuations of the populations of
eggs, nymphs, and adults of T. aguacate, how these fluctuations are related to
the incidence of avocado vegetative shoots, temperature and rainfall at 3
different altitudes in Michoacan, Mexico, i.e., 2,130 m, 1,860 m and 1,293 m.
In addition, we attempted to determine the spatial distributions of nymphs and
adults found on avocado vegetative shoots. We sampled the populations of adult
and immature T. aguacate every 20 days from Jan 2012 to Jul 2013. To estimate
population densities, 9 trees were selected in each orchard, and the trees were
distributed in the form of a cross. From each replicate of trees, 4 shoots were
randomly collected, and the eggs and nymphs were counted on them. Adults counts
were obtained from yellow traps established at the 4 cardinal points in each
tree. During the same period, young vegetative shoots, temperature and rainfall
were recorded. The results showed that this psyllid was not present at all in
the orchard located at the low altitude level of 1,293 m. The psyllid was
present at the medium altitude site from Jan to Jun, and from Dec to Jun at the
high altitude site. All of the development stages were most abundant from Mar
to May, when avocado vegetative shoots were most abundant in both years. The
abundance of eggs and nymphs showed a positive relationship with young
vegetative shoots, a negative relationship with rainfall, and the eggs showed a
positive relationship with temperature. The incidence of adults was strongly
related with spring budding, but not significantly correlated with temperature.
Both nymphs and adults had an aggregated spatial distribution.

In recent years, conservation tillage has been promoted as a method of
increasing the quality of agricultural soils; however, in the Aridisols of northeastern
Mexico, this type of tillage is not practical because of the formation of
natural crusts. Conventional tillage systems that include different culture
practices have been used for six decades to increase the yields. However,
little is known of the changes to the soil properties and modifications to the
moisture control section. Six agricultural plots representative of 78,000 ha in
districts of the state of Tamaulipas, Mexico were studied based on their
management: rainfed or irrigated, with or without the incorporation of crop
residues and with or without plot drainage. The results show that three
moisture regimes occur in the soils according to the irrigation intensity and
plot drainage: aridic, ustic and udic. The aridic regime presents the greatest
organic carbon stock (58Mgha-1), stability of aggregates in particles &gt;2
mm in the arable layer and produces sorghum yields of up to 2.5tha-1. In the
udic regime, because of plot drainage and the incorporation of crop residue and
manure, there is high biological activity; in addition, stability of aggregates
is along the whole profile, alkalinisation and redox processes occur, and
short-cycle maize yields are up to 10tha-1. The different management practices
for intense production modify the moisture regime but do not modify the organic
carbon capture. The pedogenetic processes are related to the management
intensity and cause the Aridisols to evolve into inceptisols in less than six
decades of agricultural activity; however, only the redox processes are
expressed in their classification despite a significant amount of calcitic
features.

Yeasts and organic minerals are used in diets to improve health, productive
performance and some carcass characteristics of ruminants and non-ruminants.
Thirty-two lambs (Pelibuey×Katahdin; BW=(30.55±1.67) kg; n=8) were used in a
56-d feeding experiment to study the effects of different levels of live yeast
(Saccharomyces cerevisiae; yeast), selenium (Se) and chromium (Cr) mixed
(Se-Cr), and a mixture of yeast-Se-Cr on growth performance and carcass traits.
Animals were stratified by body weight (BW) and randomly assigned to one of
four treatments: 1) control group (0.0 g kg-1 yeast); 2) yeast (1.50 g kg-1 dry
matter intake (DMI) d-1); 3) Se-Cr premix (1.5 mg kg-1 DMI d-1 for each
mineral); and 4) yeast-Se-Cr mixture. There were no treatment effects on final
BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher (P&lt;0.05) DMI than
animals supplemented with only yeast. Average daily gain (ADG), gain:feed
ratio, chop area, dorsal fat and carcass yield were similar (P&gt;0.05)
among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed
or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass
yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and
yeast-Se-Cr increased DMI, and approximately 250 g ADG animal-1 d-1 was
produced with no negative effects on growth and health of the animals.

Context: Although adventitious shoots are produced in many tree species in
response to injury, little is known about the effects of salinity on sprouting.
Aims: The main objective was to examine the sprouting capacity of Pinus
leiophylla seedlings in relation to injury and physiological changes induced by
NaCl. Methods: Seedlings were grown in controlled-environment growth rooms and
treated with 0, 100, 150, and 200 mM NaCl. Numbers of adventitious shoots
were recorded and growth and physiological parameters measured after
64 days of treatments and following a 30-day recovery period. Results:
NaCl treatments triggered sprouting of adventitious shoots, mainly in the lower
parts of the stems. However, fewer sprouts were induced by 200 mM NaCl
compared with the lower concentration treatments. These changes were
accompanied by needle necrosis, decreased chlorophyll concentrations, seedling
dry mass, and stem diameter. Stomatal conductance, net photosynthesis, and root
hydraulic conductance decreased with increasing NaCl concentrations and did not
return to the control levels after 30 days of stress relief. Conclusions:
Pinus leiophylla has the regeneration potential when exposed to salinity.
However, very high salt concentrations induce severe physiological impairments
and, consequently, a decrease of this regeneration potential.

Mucilage from stems of cactus (Opuntia ficus-indica) “Milpa Alta” (Mm) and
“Toluca” (Mt), in a single ingredient condition and in mixture with gelatin and
beeswax, was used to prepare biopolymeric films, which were assessed in terms
of microscopic morphology, thickness, transparency, tensile strength, and
permeability to water vapor, O2, and CO2. Films based on Mm were thinner, with
higher transparency, and higher tensile strength than those of Mt, but they had
similar barrier properties to water vapor, O2, and CO2. The addition of gelatin
did not affect thickness and transparency of such films, but caused
modification of the microscopic morphology, the mechanical strength, and the
barrier properties to gases and water vapor. Furthermore, the addition of
beeswax promoted the formation of aggregates in the microscopic morphology of
films and these acquired smaller thickness, higher tensile strength, and higher
barrier properties to O2, CO2, and water vapor, which may give them better
potential to be used in the postharvest conservation area of horticultural
products, although they were less transparent.

Nineteen species of seed-beetles belonging to the subfamily Bruchinae
(Coleoptera, Chrysomelidae) were collected in Xinjiang, China. Of these, the
following four were new records for China: Bruchus affinis Frolich, 1799, B.
atomarius L., 1761, B. loti Paykull, 1800 and Kytorhinus kergoati Delobel &
Legalov, 2009. We provide an annotated checklist, illustrations and a key to
the 19 species.

Domestication is an evolutionary process that culminates with the origin of
individuals or populations that are morpho-physiologically, chemically and
genetically different from their wild, congeneric relatives. The aim of the
present study was to quantify the inter- and intra-specific variation in fruit
biomass, number of seeds, and physical characteristics of seeds in O.
streptacantha Lem., O. hyptiacantha F.A.C. Weber, O. megacantha Salm-Dyck, O.
albicarpa Scheinvar and O. ficus-indica (L.) Mill., the least, intermediate,
and most highly domesticated species. The hypothesis was that selecting larger
fruits with fewer and softer seeds (normal and aborted) during domestication
reduced the interspecific variation in fruit biomass, number of seeds, and
physical characteristics of seeds in Opuntia spp., Cactaceae. For fruits of 89
variants of the Southern Mexican Plateau, total biomass and biomass of pulp
with seeds was quantified; seed length, width, thickness and dehydrated mass
were measured, as well as hardness of normal seeds. The total number of seeds
was quantified and normal and aborted seeds were counted separately. A
randomized design, with 89 treatments (variants) and six replicates and a fruit
as experimental unit per treatment was used. The data were analysed by ANOVA,
Tukey’s multiple comparison test (p ≤ 0.05), multivariate ordination (principal
components analysis) and classification (clustering analysis). Inter-specific
analysis indicated that fruits of the most highly domesticated variants (O.
albicarpa and O. ficus-indica) had higher biomass (p ≤ 0.05), followed by those
of O. hyptiacantha and O. megacantha and wild variants of O. streptacantha, and
non-significant differences existed in seed thickness or hardness. Fruit and
pulp biomass were positively and significantly correlated with seed biomass.
Species with greater domestication clustered according to their larger fruits
(≥117.83 g) and the greater number of aborted seeds (≥65). Domestication of
Opuntia has also modified seed dimensions and increased the number of aborted
seeds per fruit (≤11 to ≥65).

Nopal (edible cactus stems, Opuntia spp.) is consumed and produced in
México and the selection criteria for its export include only color, size and
the absence of deformations seen by producers at the time of harvest. The
objective of this study was to evaluate the physical and chemical
characteristics of nopal for export and to contrast them with those of nopal
for national consumption. The hypothesis was that the subjective selection of
the two types of nopal by producers is related to physical characteristics and
indirectly, to composition. The experimental design was completely random with
factorial arrangement, with two factors and two levels (factor 1: destination,
nopal for national consumption and for export; factor 2: groups of producers,
Grupo PRONACUA and Grupo Agrícola Ixquitlán), and 50 repetitions (each one
represented by one nopal). The study was performed in Otumba and San Martín de las Pirámides, Estado
de México, México. The results were analyzed with ANOVA and Tukey’s
multiple means comparison. The characteristics of the nopal samples evaluated
were: weight, length, width, thickness, firmness and number of leaves, and
content of moisture, mucilage, malic acid, chlorophyll and carotenoids. The presence
of pesticides was also determined. Export nopales had significantly lower
(p≤0.05) weight (38 g), length (2.2 cm), width (1 cm), apical thickness (0.8
cm), basal thickness (0.8 cm), moisture (0.3 %) and titratable acidity
expressed as the malic acid content (0.2 %), and content of chlorophyll (0.46
mg 100 g-1) and carotenoids (0.1 mmol g-1) higher than those selected for
national consumption; and both groups were free from the 20 most common
pesticides used in vegetables. The physical characteristics and chemical
composition of nopales for export are different than those destined for
national consumption, and they could be used to complement the quality norms to
help producers secure and increase the international market.

In situ conservation of genetic diversity in maize (Zea mays L.) has been
made for years by traditional farmers, through planting native populations, as
is the case of the Jala landrace, whose preservation is threatened by urban growth
and natural factors. The distinctive characteristics of this landrace, such as
plant height and ear length, have become dimibished. The number of farmers who
grow in situ population of the Jala landrace is low, and seed of this landrace
is often exchanged among them. For these reasons, it is relevant to assess
whether or not there is phenotypic variation among current, conserved
populations of the Jala landrace in Jala, Nayarit, México, its place of origin
and primary distribution. In situ morphological characterization of 18 Jala
landrace populations and seven controls were evaluated in 2010 using a 5 x 5
Lattice design with two replications, at three environments within the Jala
Valley. With the averages of variables through environments, a combined analysis
of variance, Tukey’s mean comparison, principal component analysis (PCA) and
cluster analysis (ADC) were performed. PCA defined that the most influential
variables for explaining the observed variation were ear length, plant height
and cob height. ACD defined three groups of populations, in which there was
greater phenotypic similarity with most of the current populations. It is
concluded that in the Jala maize landrace there is low phenotypic variation
among current in situ conserved populations, with a presumably reduced and
common genetic base.

In Central America, the traditional cropping system milpa de año (summer
season) and tornamilpa (winter season) were compared over 3 yr (2007-2009). Our
experimental objectives were to measure the performance of a maize (Zea mays
L.)-velvet bean [Mucuna pruriens (L.) DC. subsp. utilis (Wight) Burck] milpa
system throughout the summer and winter cultivation, to detect any problems associated
with velvet bean use, and to determine the contribution of this tropical legume
to soil fertility and maize productivity. In each crop season (separated in
space and time) we used a completely randomized design with a 2 × 2 factorial
arrangement of treatments with five repetitions each: without velvet bean and
without fertilizer (-V-F), with velvet bean and without fertilizer (+V-F),
without velvet bean and with fertilizer (-V+F), and with velvet bean and with
fertilizer (+V+F). Results showed that in the winter milpas the presence of
velvet bean significantly increased the soil pH, organic matter content, total
N, and decreased soil bulk density. In both cycles (winter and summer),
treatment with velvet bean (+V) produced higher grain yield, while the
treatment without velvet bean (-V) had a lower production. We concluded that
the use of velvet bean in the winter milpa contributed to the restoration of
soil fertility and increased yield maize in agricultural systems of the
small-holder farmers based on low external input.

A simulation model was developed to predict the average daily gain (ADG) in
lambs fed high-grain diets. The model is deterministic and is based on the
energy intake estimated from the digestibility of the ration as well as based
on the California Net Energy System. The model was evaluated using data from
eight experiments (28 treatments), with diets containing 50-72% grain. The ADG estimated
with the model (244 ± 44g/d) was similar to the observed ADG (249 ± 44g/d; t
test, P=0.70). The model was described by the following equation: Y=40.96 +
0.85X (r2=0.74; P&lt;0.001), with an ADG residual value of -4.6 ± 23g. A
statistical evaluation indicated a mean bias value of 4.6, a root mean square
error of prediction of 23, and a concordance correlation coefficient of 0.86.
The results indicate that the gain can be predicted in finishing lambs with an
acceptable accuracy and precision according to the developed model, with an
underestimation of 1.85%.

In Mexico, 44 thousand hectares are planted with tomatillo or husk tomato
(Physalis philadelphica Lam.), which occupies fourth place among the country’s
vegetable species. However, research on this species is scarce, especially that
related to the process of seed deterioration. We studied the effects of
deterioration in tomatillo seed, var. CHF1-Chapingo, stored from 2-mo up to 7
yr with no climate control, 18.2 ± 5 °C and 41 ± 10% relative humidity, on
physiological and biochemical variables during germination. It was found that
germination, vigor, and respiratory activity decrease significantly from the
first year of storage; thus, after 7 yr, germination and vigor decreased 99%,
and respiratory activity of seed after 48 h imbibition decreased 78%. Linoleic
acid (unsaturated) content correlated positively with germination (R = 0.78**)
and with speed of radicle emergence (R = 0.79**). Germination correlated with
speed of radicle emergence (R = 0.99**) and with respiratory activity after 48
h of imbibition (R = 0.79**). Both respiratory activity and fatty acid content
are involved in natural deterioration of tomatillo seed.

Ectomycorrhizal (ECM) fungal communities have been relatively poorly
documented in neotropical forests. We analyzed the structure and diversity of
the ECM resistant propagules present in the soil of Mexican neotropical forests
dominated by Pinus montezumae. Soil samples were collected under mature P.
montezumae, and microcosms were set up with bioassayed seedlings. The ECM
propagules were formed by relatively few taxa that were evenly distributed
across the sampled area. Some taxa, such as Rhizopogon spp. and Atheliaceae sp.,
formed an extensive mycelial system, which is likely to confer them with an
advantage for seedling colonization. We also compared the species composition
of the ECM propagules with the ECM communities previously assessed on the roots
of seedlings and adult trees. They were represented by different taxa, although
similarity analyses did not detect differences in species occurrence. Only two
taxa, belonging to the Atheliaceae family, were shared between field and
bioassayed seedlings, whereas 12 taxa were common to field seedlings and adult
trees. The lower similarity between bioassayed and field seedlings suggests
that fungal taxa found as resistant propagules are not active in mycelial
networks in field conditions and that mycorrhizal network-mediated colonization
may be prevalent in this neotropical forest.

Within the diversity of maize (Zea mays L.) in México, one of the most
interesting genetic groups is the Mexican Pyramidal Complex grown in the
Central highlands of the country. This study assessed the morphological and
agronomic diversity in a large sample of populations of the seven races of
maize most commonly cultivated in the highlands of Central México (Arrocillo
Amarillo, Chalqueño, Cónico, Elotes Cónicos, Cacahuacintle, Palomero Toluqueño
and Purépecha), and to register information of characteristics that describe
the prevailing variation of the races under study. Field experiments were
established during the 2010 Spring-Summer agricultural season with 119
representative accessions of the aforementioned races of maize, at Ciudad
Serdán and San Mateo Capultitlán, Puebla, and at Montecillo, State of México,
using an 11 × 11 simple lattice experimental design. Thirty-two quantitative
traits were recorded and submitted to analysis of variance, and 13 of those
traits were selected based on their repeatability and correlation coefficients,
for applying multivariate analyses. Analysis of variance showed highly significant
differences among genotypes for all the analyzed traits. The dispersion of
accessions ended up as a continuum distributed throughout the Cartesian plane
formed by the first two principal components, mainly influenced by traits
related to ear and kernel size (ear length, kernel width and thickness, and the
ratio kernel width/kernel length), as well as days to female flowering and
number of leaves above the ear. The traits less affected by the environment
were the most appropriate ones for grouping the accessions. Results of this
study confirmed the grouping of the accessions of previously described races,
as well as the interrelations among them as reported in previous studies;
however, our result are more precise than the former studies in defining the groups
and the interrelationships among the races because of the large sample sizes
used.

The temporal variability in nitrogen (N) transport in the Corbeira
agroforestry catchment (NW Spain) was analysed from October 2004 to September
2008. Nitrate (NO3-N) and total Kjeldahl nitrogen (TKN) loads and
concentrations were determined at various timescales (annual, seasonal and
event). The results revealed a strong intra-annual and inter-annual variability
in N transport influenced by weather patterns and consequently by the
hydrological regime. Mean annual export of total N in the catchment was
5.5kgha-1year-1, with NO3-N being the dominant form. Runoff events comprised
10% of the study period but contributed 40 and 61% of the total NO3-N and TKN
loads, respectively. The NO3-N and TKN concentrations were higher during runoff
events than under baseflow conditions, pointing to diffuse sources of N. The
mobilization of TKN during runoff events was attributed to surface runoff,
while NO3-N might be related to subsurface and groundwater flow. Runoff events
were characterized by high variability in N loads and concentrations. Higher
variability was observed in N loads than in N concentrations, indicating that
event magnitude plays an important role in N transport in this catchment; event
magnitude explained approximately 96% of the NO3-N load. However, a combination
of variables related to runoff event intensity (rainfall, discharge increase
and kinetic energy) explained only 66% of the TKN load.

Tamarixia triozae (Burks) (Hymenoptera: Eulophidae) is an important
parasitoid of the potato psyllid, Bactericera cockerelli Sulc (Hemiptera:
Triozidae). We quantified the biology and life table parameters of T. triozae
parasitizing B. cockerelli nymphs under laboratory conditions (26 ± 2 °C,
60 ± 10 % RH and 14:10 [L:D] h). Parasitoid developmental times
were 1.5, 3.5, 5.7 days for eggs, larvae and pupae respectively, with an
average of 12.0 days from egg to adult emergence. Female pupae took 0.4
day longer to develop than male pupae. Adult females lived
19.9 ± 4.5 days and had a 1.9 ± 0.8 days
preoviposition period. Each female laid an average of 165.4 ± 45.2
eggs during her lifetime. The net reproductive rate (R0), generation time (T),
intrinsic rate of increase (rm), doubling time (DT) and the finite rate of
increase (λ) were
130.9, 18.72, 0.26, 2.7, and 1.3 respectively. The potential for the use of T.
triozae as a biological control agent of B. cockerelli is discussed.

The purpose of this study was to determine how feeding sheep coffee pulp
affects carcass characteristics and what changes occur in physicochemical,
antioxidant capacity and oxidation of the meat during refrigerated storage. The
experiment was carried out in 15 Blackbelly lambs weighing an average 22.86±0.76kg.
The animals were assigned to three treatments: T0=control diet, T1=diet with 8%
coffee pulp, and T2=diet with 16% coffee pulp. After fattening for 56 days, the
sheep were slaughtered and the carcasses assessed. The inclusion of 16% coffee
pulp in the diet increased carcass dressing from 48.19 to 50.83% and decreased
the amount of fat in rumen and intestines from 3.43 to 2.53% (P<0.05). The
inclusion of coffee pulp in the diet did not alter the amount of crude protein
or fat in meat or its oxidation and antioxidant capacity during refrigerated
storage. However, the inclusion of coffee pulp in the diet decreased fat in the
rumen and intestines, and thus increased the amount of usable meat.

The genus Polianthes belongs to Asparagaceae, subfamily Agavoideae (APG
III, 2009) and is endemic to Mexico, spanning the states of Chihuahua and
Tamaulipas in the north, and extending to the state of Oaxaca in the south. Its
species are perennial, herbaceous plants with corms and bulbs. Their leaves are
green or glaucous, linear or lanceolate. Inflorescences are in racemes or
spikes with narrow and widely infundibuliform flowers, varying in color from
white to red. The fruit is a capsule with black seeds. The number of species of
Polianthes varies depending on the criteria to classify them. For example, in
the first revision for the genus, Rose (1903) recognized 12 species. According
to Espejo and López (1992), the genus has 15 species, whereas GarcíaMendoza and
Galván (1995) reported 12 species, and Solano and Feria (2007) recognized 14
species and three varieties.

Endosulfan (EN), chlorpyrifos (CRP) and chlorothalonil (CTL) are
carcinogenic and toxic pesticides in the environment, by which bioremediation
efficient actions must be directed for detoxifying contaminated systems. Fungi
such as Phanerochaete chrysosporium (PC), Trametes versicolor (TV) and some
species of Trichoderma (TRI), Mucor, Fusarium and Penicillium are able to
degrade pesticides. Seven fungal strains were isolated from agricultural soil,
wheat straw, and wheat straw pieces. The seven fungal strains as well as three
referential fungi (PC, TV and TRI) were cultivated by triplicate in Petri
dishes with minimal mineral medium contaminated with increased doses of EN, CRP
or CTL for 18 days. The mycelial growth (MG) and the percentage of growth
inhibition (PGI) were determined. The three pesticides negatively affected the
MG, but the fungal recovery was observed after 72 h for EN and CRP. At 18 days,
strains K14S, PC, TV and TRI showed total recovery when exposed to EN. In
contrast, all fungal strains showed a recovery to CRP at the 10th day. The MG
for most fungal strains was significantly inhibited (P &lt; 0.0001) due to
during CTL at 18 days. The fungicide CTL resulted in highest PGI, but strains
K8S, K14S, K11TP, PC and TV were less affected. The fungal strains K12P, K8S,
K14S, and K11TP showed acceptable tolerance to the three pesticides comparable
to PC, TV and TRI. These four fungal strains are good candidates for being used
for pesticide bioremediation.

The maize weevil Sitophilus zeamais Motschulsky is a worldwide key pest of
stored products. Usually contact insecticides or fumigants are used against it,
but problems as toxic residues, human intoxications, and resistance have
triggered the search for alternative control methods as the use of essential
oils. The objective of this research was to assess under laboratory conditions,
the insecticidal properties of Laurelia sempervirens (Ruiz &amp; Pav.) Tul.
essential oil against S. zeamais. In contact toxicity bioassay assessed
treatments were 0 (control), 1.25, 2.5, 5.0, 10, 20, and 40 mL essential oil
kg-1grain and 0 (control), 25, 50, 75, 100, 125, 150, and 175 μL essential
oil L-1air in fumigant toxicity tests. The highest toxicity by contact activity
was reached by concentrations higher than 10 mL essential oil kg-1grain (100%
mortality). The same treatments totally inhibit F1. The dose of 175 μL essential
oil L-1air showed a significant toxicity by fumigant activity causing 72.5% of
dead insects. The other treatments did not surpass 5% mortality. In offspring
effect (F1) bioassay, all treatments had an insect emergence significantly
lower than the control but concentrations equal or higher than 10 mL essential
oil kg-1grain prevented the emergence of F1during the 7 wk of bioassay. The
residual effect of contact toxicity remained by 15 d. The treatments based on
essential oil lead to a weight grain loss lower than control and germination
was not affected. All assessed treatments showed repellent effect. The
essential oil of L. sempervirens has promissory perspectives to maize weevil
control.

Sitophilus zeamais is a key pest of stored cereals. The insecticidal
properties of Laurelia sempervirens powder against S. zeamais were assessed in
laboratory. The variable evaluated were mortality of adult insects by contact
and fumigant toxicity, mortality of immature insects by contact toxicity,
residual effect of powder stored under environmental or refrigerated
conditions, adult insect emergence (F1), repellency and weight reduction and
germination of maize. The concentrations evaluated were 0, 0.25, 0.5, 1.0, 2.0
and 4.0% and the experimental design was completely randomly. In contact
toxicity bioassay all treatments showed mortality over 90% while fumigant
activity did not exceed 40%. The F1 only was registered in treatment of 0.25%
and control showing all other treatments 0%. In immature control bioassay all
treatments exhibited statistical differences with control. The storage of
powder under refrigerated conditions not improved the residual effect. All
concentrations of powder assessed showed repellence. Germination and grain
weight loss of maize seeds not showed significant differences with control. We
concluded that L. sempervirens has promissory perspectives to stored grain
pests control.

Because one of the main problems that Enterolobium cyclocarpum faces in the
planting site is the presence of weeds, to grow plants presenting appropriate
characteristics that enable them to overcome these adverse conditions during
reforestation appears as necessary. Therefore, after evaluating the responses
of various morphological and physiological indicators, and a quality test
experiment, the effects of three top pruning intensities (no pruning, 25% and
50% pruning) and three fertilization regimes (traditional, exponential and
conventional) were studied during nursery production. This approach was made
based on the fact that top pruning and fertilization in the nursery are
cultural practices that improve seedling quality as long as the pruning intensity
and fertilization regime are appropriate. There was no synergy between the two
practices; however, each factor infuenced independently on the indicators
evaluated. Top pruning at 25% and 50% did not improve the characteristics of E.
cyclocarpum. However, the nutrient supply in a conventional way had a favorable
effect when compared with other fertilization regimes. The results provided by
the quality test established that conventional fertilization allows plants to
perform satisfactorily when nutrient availability is limited.

Plants of chilli Capsicum annuum L. CM334 show a high level of resistance
to Phytophthora capsici, but are susceptible to Nacobbus aberrans; such
resistance has been associated with capsidiol accumulation, a sesquiterpene
phytoalexin. In the present study the expression of hydroxymethylglutaryl-CoA
reductase 2 gene (HMG2, associated with sesquiterpene phytoalexins
biosynthesis) in CM334 chilli roots inoculated with N. aberrans and in combination
with P. capsici, was determined by qRT-PCR. The levels of HMG2 transcripts were
significantly reduced (p≤0.05) from -1.57 to -1.28-fold in the interaction
CM334/N. aberrans; whereas in roots inoculated only with the oomycete, the
accumulation of transcripts occurred earlier and at higher levels (1.52 to
3.54-fold). In plants inoculated with both pathogens, the expression was higher
compared with those inoculated with the nematode only (p≤0.05), but generally
lower than the expression observed in roots of plants inoculated with the
oomycete alone. The expression of the HMG2 gene associated with defense was
reduced in CM334 chilli plants infected by N. aberrans.

One of the most important applications of genomic selection in maize
breeding is to predict and identify the best untested lines from biparental
populations, when the training and validation sets are derived from the same
cross. Nineteen tropical maize biparental populations evaluated in
multienvironment trials were used in this study to assess prediction accuracy
of different quantitative traits using low-density (∼200 markers)
and genotyping-by-sequencing (GBS) single-nucleotide polymorphisms (SNPs),
respectively. An extension of the Genomic Best Linear Unbiased Predictor that
incorporates genotype × environment (GE) interaction was used to predict
genotypic values; cross-validation methods were applied to quantify prediction
accuracy. Our results showed that: (1) low-density SNPs (∼200 markers)
were largely sufficient to get good prediction in biparental maize populations
for simple traits with moderate-to-high heritability, but GBS outperformed
low-density SNPs for complex traits and simple traits evaluated under stress
conditions with low-to-moderate heritability; (2) heritability and genetic
architecture of target traits affected prediction performance, prediction
accuracy of complex traits (grain yield) were consistently lower than those of
simple traits (anthesis date and plant height) and prediction accuracy under
stress conditions was consistently lower and more variable than under
well-watered conditions for all the target traits because of their poor
heritability under stress conditions; and (3) the prediction accuracy of GE
models was found to be superior to that of non-GE models for complex traits and
marginal for simple traits.